Reynolds number based verification for ultrasonic flow metering systems

Abstract

Apparatus and methods for monitoring operation of an ultrasonic flow meter. In one embodiment, an ultrasonic flow metering system includes a passage for fluid flow, an ultrasonic flow meter, and a condition monitor. The ultrasonic flow meter is configured to measure transit time of an ultrasonic signal through the fluid flowing in the passage. The condition monitor is coupled to the ultrasonic flow meter and is configured to monitor a parameter of ultrasonic meter operation with respect to Reynolds number. The condition monitor is further configured to determine whether a value of the parameter at a Reynolds number of the fluid flowing in the passage at a time associated with the value is within a predetermined range of values for the parameter at the Reynolds number.

What is claimed is:  
     
       1. An ultrasonic flow metering system, comprising:
 a passage for fluid flow; 
 an ultrasonic flow meter configured to measure transit time of an ultrasonic signal through the fluid flowing in the passage; and 
 a condition monitor coupled to the ultrasonic flow meter and configured to:
 monitor a parameter of ultrasonic meter operation with respect to Reynolds number; and 
 determine whether a value of the parameter at a Reynolds number of the fluid flowing in the passage at a time associated with the value is within a predetermined range of values for the parameter at the Reynolds number. 
 
 
     
     
       2. The system of  claim 1 , wherein the condition monitor is configured to compute the Reynolds number of the fluid flowing in the passage at the time associated with the value of the parameter. 
     
     
       3. The system of  claim 1 , wherein the parameter is selected from a set of parameters comprising ultrasonic transducer gain, flow profile factor, symmetry, crossflow, swirl, and chordal signal to noise ratio. 
     
     
       4. The system of  claim 1 , wherein the condition monitor is configured to compute dynamic viscosity of the fluid flowing in the passage. 
     
     
       5. The system of  claim 4 , wherein the condition monitor is configured to compute the dynamic viscosity of the fluid flowing in the passage as a sum of products of fluid component fraction, component dynamic viscosity, and component molecular weight. 
     
     
       6. The system of  claim 4 , further comprising:
 a temperature sensor; 
 a pressure sensor; and 
 a fluid composition sensor; 
 wherein the condition monitor is configured to:
 compute density of the fluid flowing in the passage based on measurements provided by each of the temperature sensor, the pressure sensor, and the fluid composition sensor; and 
 compute the Reynolds number of the fluid flowing in the passage based on the density, measured velocity of the fluid, and the dynamic viscosity. 
 
 
     
     
       7. The system of  claim 1 , wherein the condition monitor is configured to:
 store a plurality of values of the parameter acquired during operation of the ultrasonic meter; and 
 generate a display showing:
 each of the plurality of values at the Reynolds number of the fluid flowing in the passage with respect to the value; and 
 the predetermined range of values for the parameter at each Reynolds number. 
 
 
     
     
       8. A method for verifying operation of an ultrasonic flow meter, comprising:
 acquiring, by a monitoring system, a value of a parameter of operation of the flow meter during operation of the flow meter; 
 computing, by the monitoring system, a Reynolds number of fluid flowing through the flow meter at a time corresponding to the value; 
 determining, by the monitoring system, whether the value at the Reynolds number is within a predetermined range of values for the parameter at the Reynolds number. 
 
     
     
       9. The method of  claim 8 , further comprising selecting the parameter from a group consisting of ultrasonic transducer gain, flow profile factor, symmetry, crossflow, swirl, and chordal signal to noise ratio. 
     
     
       10. The method of  claim 8 , further comprising computing dynamic viscosity of the fluid flowing through the flow meter. 
     
     
       11. The method of  claim 10 , further comprising computing the dynamic viscosity of the fluid flowing through the flow meter as a sum of products of fluid component fraction, component dynamic viscosity, and component molecular weight. 
     
     
       12. The method of  claim 10 , further comprising:
 acquiring a temperature measurement value, a pressure measurement value, and a fluid composition measurement value from sensors disposed in the fluid flowing through the flow meter; 
 computing density of the fluid flowing through the flow meter based on the temperature measurement value, the pressure measurement value, and the fluid composition measurement value; and 
 computing the Reynolds number based on the density, measured velocity of the fluid, and the dynamic viscosity. 
 
     
     
       13. The method of  claim 8 , further comprising:
 storing a plurality of values of the parameter acquired during operation of the flow meter; 
 generating a display showing:
 each of the plurality of values at the Reynolds number of the fluid flowing through the flow meter with respect to the value; and 
 the predetermined range of values for the parameter at each Reynolds number. 
 
 
     
     
       14. The method of  claim 8 , further comprising generating an alarm based on the value at the Reynolds number being outside the predetermined range of values for the parameter at the Reynolds number. 
     
     
       15. A condition monitoring system for verifying operation of an ultrasonic flow meter, comprising:
 a parameter verification engine configured to determine whether a value of a parameter of operation of the ultrasonic flow meter, at a Reynolds number of a fluid stream flowing through the ultrasonic flow meter, is within a predetermined range of values for the parameter at the Reynolds number; and 
 a Reynolds number engine configured to compute the Reynolds number of the fluid stream corresponding to the value of the parameter. 
 
     
     
       16. The system of  claim 15 , wherein the parameter is selected from a group consisting of ultrasonic transducer gain, flow profile factor, symmetry, crossflow, swirl, and chordal signal to noise ratio. 
     
     
       17. The system of  claim 15 , further comprising a dynamic viscosity computation engine configured to compute dynamic viscosity of the fluid stream. 
     
     
       18. The system of  claim 17 , wherein the dynamic viscosity computation engine is configured to compute the dynamic viscosity of the fluid stream flowing through the ultrasonic flow meter as a sum of products of fluid component fraction, component dynamic viscosity, and component molecular weight. 
     
     
       19. The system of  claim 17 , wherein the Reynolds number engine is configured to:
 acquire a temperature measurement value, a pressure measurement value, and a fluid composition measurement value from sensors disposed in the fluid stream; 
 compute density of the fluid stream based on the temperature measurement value, the pressure measurement value, and the fluid composition measurement value; and 
 compute the Reynolds number based on the density, measured velocity of the fluid, and the dynamic viscosity. 
 
     
     
       20. The system of  claim 15 , further comprising a display engine configured to generate a visual display showing:
 each of a plurality of values of the parameter at a corresponding Reynolds number; and 
 the predetermined range of values for the parameter at each Reynolds number.